


Little Blackmailer

by LadyGlinda



Category: Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: Blackmail, Dubious Consent, Fluff, M/M, Mummy would be appalled, Sherlock is a Brat, Sherlock is sixteen and he knows what he wants, Sibling Incest, Smut, Teenlock, holmescest
Language: English
Status: Completed
Published: 2018-06-01
Updated: 2018-06-01
Packaged: 2019-05-16 21:31:07
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 2,222
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14819240
Author URL: https://archiveofourown.org/users/LadyGlinda/pseuds/LadyGlinda
Summary: When Sherlock turns sixteen, Mycroft discovers that his little brother has started to smoke. Somehow this ends with Mycroft getting blackmailed to have sex with his irresistible brat of a little brother.





	Little Blackmailer

“I can’t believe you are doing that!” Mycroft looked at the cigarette in his little brother's hand, aghast.

“Can't you now.” Sherlock blew out the smoke expertly.

“Mummy's going to kill you!”

“Oh is she. She never comes into my room, Mycroft. And until Mrs Langer comes to clean up, nothing will linger here anymore. I always keep the window open when I smoke.”

“But you can't do that! You are only sixteen and it endangers your health!” In fact Sherlock had turned sixteen on this day. Mycroft had come home for this occasion and would spend the weekend in his parents' house. He still came home pretty often when his new occupation allowed it. He was missing his home and his family. Especially Sherlock… "Mummy will be really disappointed."

“Well, she doesn't know it as I said and I rarely breathe into her face…”

“I'll have to tell her.” Because if she found out after all and Sherlock told her that Mycroft had known about it and hadn't said a word, she would get at _his_ throat. Mycroft being a grown up, twenty-three-year-old man or not – Mummy was scary…

“Oh, no, please, don't do that!” Sherlock whined, all at once all wide-eyed and melodramatic. “I'll do anything if you keep quiet!” And with this he pulled his t-shirt over his head, revealing his lean, pale upper body. Then he opened his jeans. “Anything for you!” He shuffled the jeans down and he wasn’t wearing pants…

Mycroft caught himself gaping like a fish. “What are you doing, Sherlock! Why do you… Put that back on!”

“Ah, sod it, Mycroft, we both know you've been leering after me for at least three years. _You_ told me to make deductions if you will remember, and it was not a very difficult one. I waited until I was sixteen already so you wouldn't freak out.” Sherlock slipped off his socks, deliberately slowly as it seemed. Exposing his crotch. His pink, smooth balls….His whipping dick...

“But no, I…”

Sherlock rolled his eyes. “God, don't be so boring, Mycroft, or I might change my mind. You're such a bad liar.” With this he grabbed Mycroft's shoulders and pushed him towards the bed.

The older man seemed to be unable to put an end to this, with wide eyes he watched Sherlock impatiently fumbling with his flies and then working out his cock, appallingly thickening under the touch of his baby brother's long fingers. “Sherlock, no, we can't do this, what if…”

“Ah, now we are not denying it anymore and have come to the _what if Mummy finds out_ part,” Sherlock said triumphantly.

Mycroft shut his mouth. He knew he was fucked. So to speak. It was pointless to deny his desires for his little brother as Sherlock was absolutely right, and his now fully hard dick, being surprisingly expertly stroked by Sherlock's hand, was betraying any denial.

“You are so big, brother mine,” Sherlock mumbled, his eyes focused on the efforts of his hand, his tongue absently licking his bottom lip. “I wonder how much of it I'll get into my mouth…”

“Your… No, Sherlock, you…”

“Oh, I'd better lock the door I guess! Don't move!”

He knew he should tuck himself away and get out of the room, pretending nothing had happened. He was an adult for God's sake and he couldn’t be forced into a sexual relationship with his so much younger brother! If anyone found out about it, they would blame him, saying he had coerced Sherlock; nobody would believe it had been Sherlock's idea. An idea that had been fuelled by Mycroft's forbidden desires for him that he had obviously very poorly hidden, he gave him that.

How many times he had fantasized about Sherlock giving head to him, about him worshipping Sherlock's intimate parts with his tongue or pound into him. How often had he spilled all over himself, Sherlock's name on his lips. How pathetic he was… It was his fault, he had planted this crazy idea in his brother's head.

He got up when Sherlock had just sat down next to him. “This can't continue. I will leave now and we will both forget what almost happened.”

“No,” Sherlock said calmly. “If you do that, I'll tell Mummy you molested me.”

“What?! Are you out of your mind?”

“I don't know if she would believe me,” Sherlock continued coolly, “or if she would think I made it up and get mad at me. But do you want to risk that?”

“How dare you…”

“Or we just go on and have lots of fun together, and I can visit you in London and we can have even more fun in your flat until I'm finished with school and will move there myself. I could even move in with you.”

“Sherlock, you can't blackmail me like this, you…”

“Shut up, Mycroft. I want it, you want it, and we are really smart enough to make sure nobody will find out. I can keep quiet when I come; I practiced it. Can you, too?”

“You practiced…”

“With myself, obviously. And I performed blowjobs with my fingers. I took three at the same time so it's nearly as wide but they are not as long as your dick of course.” He looked down on himself. “I'm not nearly as big. Do you think it will still grow?”

“You are perfect as you are,” Mycroft answered without thinking and felt his cheeks flush. “But perhaps it will get a little longer.”

Sherlock smiled. “Perfect, that's what I am?”

“Physically, yes. Brain-wise, certainly. But…”

“Yeah, yeah, I'm a little sociopath, I know. I take what I want. And I want you, get used to it. Can we start now or do we have to waste more time with senseless arguing about stuff that will happen anyway?”

“You are such a little shit,” Mycroft said, amazed.

Sherlock winked. “That's what they say. Now get on the bed properly so I can suck my prize.”

And finally Mycroft did it, giving in. He had too much to lose to refuse Sherlock and it had always been easier to give his insolent little brother what he wanted instead of trying – and hardly ever successfully – to convince him that it wasn’t in his own interest. But of course these were just excuses as Mycroft did want it… Perhaps it would be his doom but he didn’t fight it anymore.

*****

He winced when the first thing Sherlock did was biting him.

His brother blushed and let the wide crown of his head plop out of his mouth. “Sorry. It's so big! But I'll do better.” And he immediately threw himself into it again and this time his wonderful lips – that had been the protagonists of Mycroft's fantasies many times – covered his sharp teeth and soon obscene slurping noises filled the room along with Mycroft's panting, and he felt saliva run down his shaft as Sherlock didn’t manage to enwrap him completely. Sherlock gagged and rolled his eyes a few times and noisily breathed through his running nose; in short it was rather messy and dirty and Mycroft loved every second of it.

His fingers were playing with Sherlock's curls and his delicate ears and cupping his increasingly wet chin, and he felt an overwhelming tenderness for this difficult, demanding, self-centred, brilliant, handsome boy who was his little brother.

He was not far from coming when Sherlock pulled away. He had fumbled with Mycroft's balls and squeezed them slightly and had obviously enough knowledge to realise how close Mycroft had been to climax.

“Okay, time for the next step.” He leaned forward and opened the top drawer of his nightstand. He took out a small bottle and handed it to Mycroft, then he lay down on his back and pulled up his legs.

“What…”

Sherlock sighed. “Lube me up and fuck me.”

“What? Now? We'll have to go down now and…”

“What, for seeing Aunt Canderalla and Cousin Colm? We will have to sit and drink tea with them soon enough. I wish Mummy would have spared me this shit!” He was looking furious and his blue eyes were glittering with wrath. “Get on with it, Mycroft. You are so close to coming that it will only take a few thrusts anyway.”

Mycroft was speechless. He stared at the bottle. “Peanut-butter-flavour?”

“Sounded good to me.”

“How did you even get that?! They don't have such stuff in a drugstore here.”

Sherlock grinned, his mood lightening up. “Somebody owed me a favour.”

Mycroft swallowed. “You didn’t tell anyone about your plans, did you?” Because obviously Sherlock had planned this all thoroughly…

“Of course not, what do you think I am – an imbecile? Nobody knows it and nobody ever will. Now finally get this stuff into me so you can fuck me.”

Mycroft knew this was madness. Their parents and Mummy's sister with her son were downstairs, waiting for them. Somebody could knock at the door in two minutes. And here they were – Sherlock on his back, his pink little hole exposed for him naughtily, his half-hard dick twitching on his flat stomach, waiting to get taken.

But he did as Sherlock had told him. He coated his dick with a generous amount of the strange smelling lubrication and then he prepared Sherlock's virgin – sort of as Sherlock certainly had practiced this in one way or the other as well – hole with two fingers to finally sink into a heat so tight that it immediately shut off all thoughts.

*****

Mycroft had always despised people who talked about nothing else than sex and seemed to think about nothing else, either. He had a few experiences but it had never been more than mutual fumbling and a little sucking. So it was his first time as it was Sherlock's, and it was so overwhelming that he could have screamed.

He could feel Sherlock's nails digging into his shoulders and sometimes his younger brother pulled at his hair and his ears, lost in the sensation of being taken, and Mycroft thrusted harder and deeper with every passing second. The process of opening Sherlock up thoroughly had not exactly cooled down his arousal but it had driven him a little away from the edge so he lasted longer than either of them had expected.

Nothing counted anymore – it was all about them and Mycroft knew it was only the first time of many to follow. There was no way in hell that he would let Sherlock go again. Except of course if Sherlock had only longed for a one-time experience and would soon have enough of him.

They didn’t talk but they kissed every few strokes, and his brother's lips tasted so infatuating that Mycroft moaned into his mouth every time. Sherlock smiled and winked at him when he did that for the tenths time, and Mycroft couldn’t help but grinning.

“You're really a little shit,” he finally broke the silence, thrusting especially hard to stress his point.

Sherlock groaned but only hammered his feet onto his arse to make him do it again. “Yes, and you can be happy about it. If I was a coward like you, we would not be doing this now.”

He did have a point and Mycroft nodded. “Mummy would freak out,” he said and Sherlock chuckled.

“No, she would just drop dead. But teenagers don't speak about their sex life with their parents, do they?”

“Not if they share it with their older brothers at least…”

“With whom else should I share it, Mycroft? With people that are as dumb as a branch? It was you or it was nobody.”

And this drove Mycroft over the edge. He spilled his seed into his brother's body with a muffled cry, and at the same time he finally took hold of Sherlock's cock and it took only a few pumps before Sherlock released himself over his own chest, his eyes closed, his teeth working his bottom lip, but silent as he had promised.

Mycroft pulled out of him carefully and wasn’t surprised at all when Sherlock handed him a tissue so he could catch the semen that was dribbling out of his stretched-out hole, and in the meantime Sherlock wiped up the mess on his stomach.

“Well, guess we'll have to go downstairs now,” he said, shaking his head. “I would so much rather stay here. But that was the best birthday present you could make me.”

“Entirely voluntarily above all,” Mycroft said dryly.

Sherlock grinned. “Ah, as if you had believed I would really do that. I just thought you need an incentive to get over your silly doubts.”

“Nicely played, brother mine.”

“I'm not playing with you, Mycroft. Just helping you realise…”

“Realise what?” Mycroft started to dress himself, and Sherlock quickly did the same. They both needed a shower but they didn’t have time for it now. Mycroft could only hope they wouldn’t smell like sex…

“That this is how it should be. You and me, together.”

“Because we're both so smart?”

Sherlock smiled. “That's a given but no. Because you love me and I love you. I heard this is a very good reason to be together.”

There was no point in arguing that. In fact even Mycroft thought this should be the only reason.

The End

 


End file.
